From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 91E2D46B7 for ; Mon, 16 Jan 2023 16:32:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15D89C433EF; Mon, 16 Jan 2023 16:32:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673886725; bh=Ll8rBaKVoplQ3eCFPjwUmndeM7Z3aZ2wKe/glpQbtJQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fnpx0oRNH9yVW+WZG1oP7mYDgAbIzxTu4EuaQI618EJAbZ1naaHh5j2oQ8nNVWCyg adBQip0OxXj4ZEbSRZn7gGml+y/KJ38pU+2Osq2kL0eAmjplWVlvqiHcttrN91GrkK ilXrvzXa3LL78OTDxhkWRvH1SsUXpVaJwwiFJYRQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Artem Chernyshev , David Sterba , Sasha Levin Subject: [PATCH 5.4 538/658] btrfs: replace strncpy() with strscpy() Date: Mon, 16 Jan 2023 16:50:26 +0100 Message-Id: <20230116154934.137948077@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230116154909.645460653@linuxfoundation.org> References: <20230116154909.645460653@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 63d5429f68a3d4c4aa27e65a05196c17f86c41d6 ] Using strncpy() on NUL-terminated strings are deprecated. To avoid possible forming of non-terminated string strscpy() should be used. Found by Linux Verification Center (linuxtesting.org) with SVACE. CC: stable@vger.kernel.org # 4.9+ Signed-off-by: Artem Chernyshev Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/ioctl.c | 9 +++------ fs/btrfs/rcu-string.h | 6 +++++- 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 8553bd4361dd..64b443aa61ca 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3299,13 +3299,10 @@ static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info, di_args->bytes_used = btrfs_device_get_bytes_used(dev); di_args->total_bytes = btrfs_device_get_total_bytes(dev); memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); - if (dev->name) { - strncpy(di_args->path, rcu_str_deref(dev->name), - sizeof(di_args->path) - 1); - di_args->path[sizeof(di_args->path) - 1] = 0; - } else { + if (dev->name) + strscpy(di_args->path, rcu_str_deref(dev->name), sizeof(di_args->path)); + else di_args->path[0] = '\0'; - } out: rcu_read_unlock(); diff --git a/fs/btrfs/rcu-string.h b/fs/btrfs/rcu-string.h index a97dc74a4d3d..02f15321cecc 100644 --- a/fs/btrfs/rcu-string.h +++ b/fs/btrfs/rcu-string.h @@ -18,7 +18,11 @@ static inline struct rcu_string *rcu_string_strdup(const char *src, gfp_t mask) (len * sizeof(char)), mask); if (!ret) return ret; - strncpy(ret->str, src, len); + /* Warn if the source got unexpectedly truncated. */ + if (WARN_ON(strscpy(ret->str, src, len) < 0)) { + kfree(ret); + return NULL; + } return ret; } -- 2.35.1